Probiotics for Autism
Autism & Digestive Health
People with autism often have more digestive health problems than average. 1 in 4 children with autism are thought to have at least one chronic gastrointestinal symptom1 and numerous studies have discovered abnormal digestive health conditions in people with autism2,3. Autistic children have also been found to have more Clostridia ( a type of pathogenic bacteria) in the gut than children without autism4 and a recently published study5 found a little known bacterial genus called Sutterella present in microbiota in just over half the participants with autism, but in none of those without autism.
Probiotic microorganisms support digestive health in adults and children. So can probiotics help with children or adults with autism?
Probiotics for Autism: A look at the Research
Probably the most well-known clinical study into probiotics for autism was the unfinished trial run in 2006 by Professor Glenn Gibson at the University of Reading; referred to by some as the trial which was "so successful, that it failed". 40 autistic children all between 4 and 13 years old were randomly separated into a trial group, and a control group. The trial group were given a probiotic supplement with the species Lactobacillus plantarum whilst children in the other group were given placebos (read about placebo-controlled studies here). The trial was supposed to continue this way for three weeks, before the groups would switch supplements and continue as such for a further three weeks. However researchers reported that the Lactobacillus probiotics had such a positive effect on the participants, that the 'blind' aspect of the trial fell through. Parents of participants in the probiotic group could see a noticeable effect, and said it was heartbreaking to have to stop their child from taking the probiotics. Too many participants dropped out of the trial when they were supposed to switch over.
Comments from parents6 of participants in the probiotic group included not only reports on digestive health improvements, such as, 'better formed stools' but also potentially mental & behavioural improvements, such as, 'more calm, relaxed, not stressed' and 'improved ability to listen and concentrate'. However it is certainly worth mentioning that these comments are taken from a few parents, and also that interestingly, during the trial the parents' overview of the effects of the probiotics tended to be more positive than the view of the teachers. Finally, the study saw a large drop out rate which meant it could not continue.
We have not been able to ascertain which strain of the L. plantarum species was used; reports of the trial state only that this strain was non-commercial. We want to underline that the beneficial effects of probiotics are strain-specific (ie. the benefits must ideally be associated with a specific probiotic strain, and not simply a species).
Research in animal models
Whilst there are still relatively few human clinical trials investigating the link between gut flora and autism, scientists at Baylor College of medicine in Texas have recently been looking at the impacts of gut flora on the behavioural development of mice. Senior study author, Dr. Mauro Costa-Mattioli said that the inspiration for the study7 was taken from earlier human studies that have shown a correlation between maternal obesity during pregnancy and the risk of their offspring developing various neurodevelopmental disorders, including autistic spectrum disorders.
In the study, 60 female mice were fed a very high fat diet in order to make them gain weight. They were then bred, and kept with their offspring for three weeks before the young were weened on to a normal diet. After a month, it was found that the young mice all showed behavioural deficits, including spending less time in contact with other young mice, and not initiating social interactions. Both of these character traits are common in autistic spectrum disorders in humans.
In order to find out the reason behind the offspring displaying these behavioural deficits, the study team used gene sequencing to investigate the bacterial composition of their gut flora. It was found that the young that were born to these over-weight mothers had very different gut flora to a control group of mice that were born to healthy weight mothers. In particular one type of bacteria, Lactobacillus reuteri, was reduced more than nine fold in the microbiome of the mice born to the over-weight group.
Based on this finding, the research team then cultured a strain of L. reuteri, and put it in the drinking water of the unhealthy high-fat-diet offspring. They found that the inclusion of this one single strain of probiotic bacteria was enough to rectify their anti-social behaviour traits. Interestingly, the research also showed that this single strain of bacteria promoted the production of the ‘bonding hormone’ oxytocin, which is understood to play a crucial part in social behaviour in humans. A lack of oxytocin in humans has been associated with autism and autistic spectrum disorders.
More research needed
A great deal more clinical research is necessary before any firm conclusions can be made as to the effect of probiotics on autistic children and adults; preferably with large, randomised and double-blind clinical trials. Professor Gibson has expressed a desire to undertake a larger study in the future with fewer drop outs.
If you are going to recommend a probiotic to support digestive health, make sure you pick well-researched live strains. See OptiBac Probiotics 'For every day EXTRA Strength' (containing the most researched strain of acidophilus in the world, and suitable for those from 1 year and over) or OptiBac Probiotics 'For babies & children'.
Autism & Diet
Some people believe that the symptoms of autism can be controlled in part by dietary changes, hence a fair amount of those on the autistic spectrum cut out certain foods which are thought to be difficult to digest. In particular many children and adults with autism take on a gluten & casein free diet (known by many as the GF/CF diet). There is not a huge amount of clinical research on the GF/CF diet, and drawbacks could potentially include decrease in certain useful white blood cells 8 as well as difficulty in reintroducing foods containing elements of gluten or casein. However, some anecdotal evidence suggests that the GF/CF diet could not only help improve digestive health, but also to improve attention & concentration, communication and language, and social integration, amongst other behavioural changes. Other foods which people cut out or reduce include MSG and aspartame flavour-enhancing ingredients, lutein, feingold and complex carbohydrates, starches and processed sugars.
Once again, large and reliable clinical trials into the effects of diet on those on the autistic spectrum would be warmly welcomed and must be called for. It is always best for individuals to see a dietitian or nutritionist before eliminating certain foods in one's diet. In the meantime, anecdotal evidence that diet can alter the symptoms of autism provides further promise for the link between autism and gut health.
Probiotics for Autism: Anecdotal Evidence
Autism, by nature, affects different people in different ways. Of course, it is always advisable to speak to a nutritionist, and is often a case of trying certain approaches to diet or supplementation whilst carefully monitoring one's results. A few mummy bloggers have tried our probiotics for their children with autism, including Claire from Asperger's Info.
"Pretty quickly after having first started the probiotics, Little man seemed more comfortable, the last few days I have noticed that he is able to eat more of his food without it upsetting his stomach. By day six I noted that Little man wasn't nearly as bloated as he usually gets." writes Claire.
Claire's son was 11 years old at the time, and taking OptiBac Probiotics 'For every day EXTRA Strength'. The story was reported by the Daily Mail in 2014, which looked at 'Little man's' gut health, as well as mental health, including anxiety. See comments below for further anecdotes.
Have you any experience with probiotics & autism? Please share your thoughts with us via the comments box below.
1.Molloy CA. et al (2003). Prevalence of chronic gastrointestinal symptoms in children with autism and autistic spectrum disorders. Autism. 7:165-171.
2. Finegold. SM. et al (2002) Gastrointesintal microflora studies in late-onset autism. Clinical Infectious Diseases 35: S6-516.
3. Parracho H. et al (2005) Differences between the gut microflora of children with autistic spectrum disorders and that of healthy children. Journal of Medical Microbiology 54: 987 - 991.
4. Song, Yuli. et al (2004) Real-Time PCR Quantitation of Clostridia in Feces of Autistic Children. Appl Enciron Microbiol 70(11): 6459-6465.
5. Williams, BL, Hornig M, Parekh T, Lipkin WI. (2012) Application of novel PCR-based methods for detection, quantitation, and phylogenetic characterization of Sutterella species in intestinal biopsy samples from children with autism and gastrointestinal disturbances. mBio 3(1):e00261-11. doi:10.1128/mBio.00261-11
7. Single species of gut bacteria can reverse autism-related social behaviour in mice. Baylor College of MedicineBaylor College of Medicine NewsNeuroscienceSingle species of gut bacteria can reverse autism-related social behavior in mice.
8. Ashwood P. et al (2003). Intestinal lymphoctye populations in children with regressive autism: evidence for extensive mucosal immunopathology. Journal of Clinical Immunology 23: 504-517.
Please note that the views & comments expressed on the blogs mentioned above are not our own, nor are they endorsed by OptiBac Probiotics.